A device which performs driving assisting using time-series traffic signal information regarding the lighting state of a traffic signal has been proposed. For example, Patent Literature 1 discloses a system in which a DSRC transmitter, which transmits the traffic signal information, is provided in a traffic signal and an in-vehicle device is mounted in a vehicle. In this system, the traffic signal information is received by a DSRC receiver of the in-vehicle device, the lighting state and the change timing of the traffic signal are acquired from the received information, and the lighting state and the change timing of the traffic signal are displayed on a display device of the in-vehicle device so that the driver can drive after recognizing a time until the lighting state of the traffic signal changes.    Patent Literature 1: Japanese Unexamined Patent Application Publication No. 2004-171459